1. Field of Invention
The invention relates to the method of using ionic liquids to improve the lubrication effect of synthetic, mineral and native oils during operation of chains, steel belts, wheel bearings, roller bearings, and electric motors. In particular the invention relates to such a method in which an improved lubricating composition that is protected against thermal and oxidative attack enables operation of chains, steel belts, wheel bearings, roller bearings, and electric motors for at least 48 hours by reducing the evaporation loss and the lackification tendency of the lubricant.
2. Description of Related Art
Lubricants are used in automotive engineering, conveyor technology, mechanical engineering, office technology and in industrial factories and machines but also in the fields of household appliances and entertainment electronics.
In roller bearings, sliding bearings (contacts) and friction bearings, lubricants ensure that a separating film of lubricant which transfers the load is built up between parts rolling or sliding against one another. This achieves the result that the metallic surfaces do not come in contact and therefore no wear occurs. These lubricants must therefore meet high demands, which include extreme operating conditions such as very high or very low rotational speeds, high temperatures due to high rotational speeds or due to outside heating, very low temperatures, e.g., in bearings that operate in a cold environment or that occur with use in aeronautics and space travel. Likewise, modern lubricants should be usable under so-called clean room conditions to prevent contamination of the clean room due to abrasion and/or consumption of lubricants. Furthermore, when using modern lubricants, they should be prevented from vaporizing and therefore “lackifying,” i.e., becoming solid after a brief use and therefore no longer having a lubricating effect. Special demands are also made of lubricants during use, so that the running properties of the bearings are not attacked thanks to low friction, the bearings must run with a low noise level and with long running times must be achieved without relubrication. Lubricants must also resist the action of forces such as centrifugal force, gravitational force and vibrations.
The service life and lubricating effect of synthetic, mineral and native oils are limited by their thermal and oxidative degradation. Therefore, amine and/or phenolic compounds have been used in the past as antioxidants, but they have the disadvantage that they have a high vapor pressure and a short lifetime, which is why the oils “lackify” after a relatively short period of use, i.e., they become solid and therefore can cause major damage to the equipment especially in the area of roller bearings, sliding bearings (contacts) and friction bearings.